ABSTRACT
Cystic echinococcosis, known as hydatidosis, is a parasitic zoonosis caused by the larvae of Echinococcus granulosus. Renal hydatidosis is a very rare condition, representing 1% to 2% of cases. We present an 18-year-old patient who, after suffering a trauma, experienced severe lower back pain and persistent gross hematuria disproportionate to the trauma. Ultrasonography and tomography revealed cystic images compatible with right renal hydatidosis and hemoperitoneum. In addition, rapid clinical deterioration was observed with decreased hematocrit, leading to lumpectomy with abundant cysts inside and outside the right kidney, without viable parenchyma. Therefore, a total nephrectomy was performed. The patient was discharged with albendazole treatment. Pathological anatomic analysis confirmed the diagnosis of hydatidosis. Surgery remains the best therapeutic option. The use of ultrasonography improves the early detection of zoonosis, especially in pediatric patients, and favors the use of more conservative therapeutic techniques.